We plan to evaluate long-term effects of recurrent and chronic otitis media in the first years of life on various developmental characteristics of children at the ages of 5 years, 9-11 years, and 15-17 years. A common complication of otitis media is hearing loss. This generally is transient and low-level, but occasionally permanent and more severe. The problem that we want to address is whether recurrent or chronic even minimal auditory deficiencies accompanying otitis media will interfere with language acquisition and cognitive development. This research project will be based on already assembled data of the Child Health and Development Studies. These are prospective longitudinal studies of pregnancy, delivery, and child development; the population consists of members of a prepaid medical insurance, program, Kaiser Foundation Health Plan.